Cisco DFA (Dynamic Fabic Architecture), aka Vinci

This week Cisco announced what amounts to a total re-work to their existing FabricPath virtualized multi-tenant data center design. The marketing name given to this DFA – Dynamic Fabric Architecture, aka – Vinci. The aim is to accomplish a dynamically configured data center fabric.

Summary: Fundamentally what’s new with DFA is pushing layer 3 to the access-edge/leaf while still allowing any host to reside on any leaf in the fabric. This takes the load off of the spine to have to do any learning, routes or MAC, thus the spine becomes something akin to an MPLS core router. The last major component of DFA is the reworking of DCNM to enable it to be more of an auto-provisioning and fabric orchestration tool.

How it works: If you understand FabricPath and conversational learning then you are well on the way to understanding DFA. As you may expect FabricPath is the core connectivity protocol. However, by using an anycast IP on the leaf plus MP-iBGP (over IS-IS) to carry the learned hosts/prefixes enables layer 3 at the edge. Along with some other mechanisms running in the background such as proxy ARP, this allows any VM/host to be connected to any leaf node.

Spine and leaf is just an application of folded Clos. At first I didn’t know what you were talking about but I re-read the blog post and that bullet point about spine & leaf support but prefer folded Clos … I have no idea what I meant by that.